The present invention is related to a method for formulating particles from solutions for processing in a fluid bed.
For drying known methods are utilizing among others mixture of solutions where the dried end product is mixed with a return flow with the product. Such a method, however, includes very different resting times for the product which is recirculated in relation to products not being recirculated. Additionally the flow of products substantially is increased through the drying chamber.
The solution is spread out or in other way laid on inert particles having a layer which thereafter is dried. The layer is peeled in the drying chamber thereafter to be taken out as dried powder in a cyclon, or the particles are taken out of the chamber for peeling. Such a method easily pollutes the dried product from the inert particles. Furthermore, the inert particles which substantially do not pollute, are relatively heavy particles needing very large amounts of energy supplied to the fans to maintain the particles in fluidized condition.
With the method according to the present invention substantial advantages are achieved in relation to known methods, whereby the advantages with the known method substantially are maintained and the disadvantages avoided. In this way a strongly reduced recilient time is achieved, strongly reduced flow of products through the dryer, no pollution of the product from the inert particles, reduced claim for energy for the fans and furthermore also a possibility to control the density and porousity of the end product.